Current Electri...

Assertion In a simple battery circuit the point of lowest potential is positive terminal of the battery.
Reason The current flows towards the point of the higher potential as it flows in such a circuit from the negative to the positive terminal.

Assertion The temperature coefficient of resistance is positive for metals and negative for p-type semiconductor.
Reason The effective charge carriers in metals are negatively charged whereas in p-type semiconductor they are positively charged.

Assertion In the following circuit e.m.f is 2V and internal resistance of the cell is 1 Ω and R = 1 Ω, then reading of the voltmeter is 1 V.
Reason V = E – ir where E = 2V, i = 2/2 = 1A and 2 R = 1 Ω

Assertion There is no current in the metals in the absence of electric field.
Reason Motion of free electrons is random.

Assertion Electric appliances with metallic body have three connections, whereas an electric bulb has a two pin connection.
Reason Three pin connections reduce heating of connecting wires.

Assertion The drift velocity of electrons in a metallic wire will decrease, if the temperature of the wire is increased.
Reason On increasing temperature, conductivity of metallic wire decreases.

Assertion The electric bulbs glows immediately when switch is on.
Reason The drift velocity of electrons in a metallic wire is very high.

Assertion Bending a wire does not effect electrical resistance.
Reason Resistance of wire is proportional to resistivity of material.

Assertion In meter bridge experiment, a high resistance is always connected in series with a galvanometer.
Reason As resistance increases current through the circuit increases.

Assertion Voltameter measures current more accurately than ammeter.
Reason Relative error will be small if measured from voltameter.